Sister Light, Sister Dark (1988) by Jane Yolen is a curious feminist fantasy, though better called a human-scale fantasy, centering around the prophecy of the Anna, yet also centering around the coming of age of Jenna. When this tale is following its own voice, this curious tale works, going where you expect but never quite how you expected, or why. This is not a work where the heroine jauntily lopes along, from one fight to another. This is very much an internal story with external features. Where the novel falls down is when it hews too close to trope, too close to what it should be.
By human scale fantasy, I mean that the book pays great attention to the people in it, giving them time to act, react, and consider, letting us get to know them.
The book is only the beginning of the tale, for the Great Alta saga covers three books. There's much left to be done. I found the wrap-up for this book quite unsatisfactory as any stand-alone conclusion, so just aim to read the whole batch when you get started.
Magic doesn't play a large place in the fantasy even while it does. The magic here isn't the magic of spells and world alteration, but a subtler magic, one that's structural to the narrative, not easily produced or reproduced. I find the low-key stakes of magic quite welcome and more compelling than world-shaking spellcasters. The magic here means something to the people who have it, shaping their world.
While the tale does have prophecy, the tale undercuts that prophecy just as much as it sustains it. In the end, the character must do as she must, making her decisions as she goes.
If you like to think about your fantasies, and don't care so much for fight scenes, then this is a book for you.